KR920008898B1 - Circuit for controlling head speed of fax - Google Patents

Abstract

The system is for controlling the speed of printing by counting the number of black & white pixels in one line, comparing the counted number with a initial proportion of black & white pixels, and outputting the strobo signal applied to a thermal head sequentially or simultaneously in block and line unit according to the compared data quantity system includes a multiplexer (2) for converting the parallel image data of one line to serial image data, a NAND gate (3), a counter (4), an I/O section (5) for interfacing the black & white pixels counted by the counter (4), a microprocessor (6) for outputting strobo signal S(S1-S8), and a buffer section (8) for heating a thermal head (9) according to the strobo signals (S1-S8).

Description

Facsimile's print speed control system

1 is a system configuration diagram of a conventional facsimile.

2 is a detailed block diagram of the thermal recording head of FIG.

FIG. 3 is a waveform diagram of a strobe signal of FIG.

Figure 4 is a schematic diagram of a printing speed control system of the present invention.

5 is an input / output timing diagram of each part of FIG.

FIG. 6 is a block unit strobe waveform diagram of the microcomputer according to FIG. 4. FIG.

7 is a line-by-line strobe waveform diagram of the microcomputer according to FIG.

8 is a signal flow diagram for the operation description of FIG.

* Explanation of symbols for the main parts of the drawings

1: line memory part 2: multiplexer part

3: NAND gate 4: Counting unit

5: input / output unit 6: microcomputer

The present invention relates to a printing speed control in a receiving unit of a facsimile. More specifically, a line of black pixels read from a reading unit is counted and compared with an initial black pixel ratio. The present invention relates to a printing speed control system of a facsimile, which is designed to increase the speed of printing by sequential short or block short by line and line.

Conventional facsimile is shown in Figure 1 and 2 of the accompanying drawings, the microcomputer 100 for controlling the overall operation of the system according to the program execution of the program ROM 104, and the control of the microcomputer 100 A line memory section 101 for storing image data read from a reading unit (not shown in the drawing) and outputting the stored image data according to a signal, and a buffer for buffering the image data output from the line memory section 101. A heat-sensing recording head 103 which heats the heat generating elements 103a-103d and the heat generating resistors R0-R26 with the straw signal output from the microcomputer 100 and prints the data of the buffer 102. It consists of).

The printing process of the conventional facsimile machine configured as described above will be described with reference to FIG.

First, when the microcomputer 100 controls the line memory unit 101 through the control line according to the program execution of the program ROM 104, the line memory unit 101 stores image data sequentially input from the reading unit. Thereafter, each time the image data of one line inputted from the reading unit is completed, the line memory unit 101 inputs it to the microcomputer 100 through the control line, and the microcomputer 100 includes the line memory unit ( In accordance with the control signal input from 101, the corresponding address of the line memory unit 101 is designated through the address line to input image data to the buffer unit 102, and through the control data line, FIGS. Similarly, one line of strobe signals ST1-ST4 are sequentially output in accordance with the size of the thermal recording paper and input to the heat generating elements 103a-103d of the thermal recording head 103. FIG. Accordingly, the thermal recording head 103 generates the heat generating elements 103a-103d and the heat generating resistors R0-R26 in response to the strobe signals ST1-ST4 sequentially input from the microcomputer 100 to generate the buffer unit 102. Each line of image data buffered and inputted from the above) is printed on one line of the thermal recording paper.

However, in the conventional facsimile, the microcomputer sequentially inputs a strobe signal (ST1-ST4) corresponding to one line of data into the thermal recording head and prints one line on the thermal recording paper. If 1728 pixels of phosphorus and 1728 pieces of line data received from the reading unit are less than 1728, the microcomputer sequentially drives the strobe signals ST1-ST4 by outputting the strobe signal regardless of the amount of data. There was a problem that the waste of time and print speed is reduced by outputting up to ST4).

Therefore, an object of the present invention is to count a line of black pixels read from a read out, compare them with an initial black pixel ratio, and sequentially strobe signals input to the thermal recording head in block units and line units according to the compared data amount. The present invention provides a facsimile print speed control system for controlling a print speed by outputting or simultaneously printing.

An object of the present invention as described above is a multiplexer unit for outputting one line of image data input in parallel from a line memory as serial image data, and a NAND gate for NANDizing image data output in series from the multiplexer unit. And a count unit for counting the output clock pulses of the NAND gate, an input / output unit for signal processing the clock pulses counted from the count unit, a count value input from the input / output unit, and a set initial black pixel ratio. According to the comparison result, the microcomputer outputs the strobe signal simultaneously in block units and sequentially outputs in line units, the buffer unit for buffering the strobe signal output from the micom, and the multiplexer unit generates heat according to the strobe signal of the buffer unit. It consists of a thermal recording head that prints serial image data. Writing, to be achieved, or less will be described in detail based on the accompanying drawings, the present invention.

4 is a configuration diagram of a printing speed control system of the present invention, and as shown therein, a line memory unit 1 for storing image data input by binarization from a reading unit (not shown) in units of lines; A multiplexer section (2) for converting and outputting one line of image data output in parallel from the line memory section (1) into serial image data, and the image data serially converted from the multiplexer section (2) and input clock pulses. (CLK) and the NAND gate 3 to digitize, a count unit 4 for counting clock pulses sequentially input from the NAND gate 3, and a clock pulse counted from the count unit 4. The input / output unit 5 and the count value input from the input / output unit 5 and the set initial black pixel ratio are compared according to the execution of the program of the main microcomputer 7, The microcomputer 6 outputs the signal simultaneously in block units and sequentially outputs in line units, a buffer unit 8 for buffering the strobe signal output from the microcomputer 6, and the buffer unit 8 It consists of a thermal recording head 9 which generates heat in accordance with the strobe signal and prints serial image data of the multiplexer section 2.

The thermal recording head 9 includes a shift register section 9a for shifting image data sequentially output from the multiplexer section 2, and a latch section 9b for latching image data of the shift register section 9a. And the AND gates A1-A8 that generate heat generation resistors R1-R8 in response to the strobe signal of the buffer section 8 to print image data of the latch section 9b on the thermal recording paper.

The operation and effects of the present invention configured as described above will be described in detail with reference to FIGS. 4 to 8.

First, when the binarized image data is input from the reading unit, the line memory unit 1 stores the input image data. Thereafter, when one line of image data is stored, the line memory unit 1 inputs the stored one-byte image data in parallel to the multiplexer unit 2, and the multiplexer unit 2 is a line memory. One-byte image data input in parallel from the sub-1 is converted into serial image data as shown in FIG. 5B and applied to one input terminal of the NAND gate 3. At this time, if the clock pulse CLK as shown in FIG. 5A is input to the other input terminal of the NAND gate 3, the NAND gate 3 is one-byte image data and clock inputted in series from the multiplexer unit 2. The pulse CL is NANDed as shown in FIG. 5C to be input to the counting unit 4. The counting unit 4 counts the clock of the current black pixel sequentially input from the NAND gate 3 to the input / output unit 5. Input to the microcomputer (6).

Accordingly, the microcomputer 6 compares the value of the black pixel with the preset reference seconds according to the program execution of the main microcomputer 7 and the current black pixel amount counted from the counting unit 4, and the reference seconds are higher than the current black pixel. As many times as possible, the strobe signals S1-S8 as shown in FIGS. 7A to 7I are simultaneously output in line units and input to the buffer unit 8, and the buffer unit 8 inputs the strobe signals S1-S8. Is buffered to heat the heat generating resistors R1-R8 simultaneously through the AND gates A1-A8 of the heat-sensitive recording head 9, and simultaneously outputs an enable signal as shown in FIG. By enabling the latch portion 9b of the < RTI ID = 0.0 > 1), < / RTI > Printed on one line of thermal recording paper at high speed through A1-A8). . When the reference initial black pixel ratio is smaller than the current black pixel, the strobe signals S1-S8 shown in FIGS. 6A through 6I are sequentially output in block units and input to the buffer unit 8 as a result of the comparison. The buffer unit 8 sequentially buffers the strobe signals S1-S8 that are sequentially input to generate heat generation resistors R1-R8 through the AND gates A1-A8 of the thermal recording head 9. In addition, by enabling and outputting an enable signal as shown in FIG. 6A to the latch portion 9b of the thermal recording head 9, one line of image data stored in the latch portion 9b is sequentially arranged on one line of the thermal recording paper. Is printed.

As described in detail above, the present invention sets the black pixel amount of the reference value rather than the conventional block-based printing method, so that printing can be performed on a line-by-line basis and the timing for shortening the thermal recording head is set. By reducing it, the thermal recording paper can be printed at the right speed.

Claims (1)

A multiplexer unit 2 converts and outputs one line of image data input in parallel from the line memory unit into serial image data, and NANDizes the image data output from the multiplexer unit 2 with an input clock pulse CLK. A NAND gate 3, a counting unit 4 for counting clocks of the black pixels sequentially input from the NAND gate 3, and an input / output unit 5 for interfacing the black pixel pulses counted from the counting unit 4; And a microcomputer that compares the black pixel count value input from the input / output unit 5 with the set reference initial black pixel amount and sequentially and simultaneously outputs the strobe signals S1-S8 in block units and line units according to the result of the comparison. (6) and a buffer unit (8) for buffering the strobe signals (ST1-ST8) output from the microcomputer (6) to sequentially and simultaneously heat the thermal recording head (9) in blocks and lines. Facsimile Milly print speed control.

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